Production of permanent lustrous finishes on fabrics



Patented Oct. 10, 1950 PRODUCTION OF PERMANENT LUSTROUS FINISHES ON FABRICS Arnold L. 'Lippert, Wilmington, Del., assignor to Joseph Bancroft & Sons 00., Wilmington, Del., a corporation of Delaware No Drawing.

Application June 17, 1947, Serial No. 755,246. In France April 1, 1939 Section 1, Public Law 690, August 8, 1946 Patent expires April 1, 1959 Claims. 1

This invention relates to the art of producing permanent lustrous finishes on fabric of the type commonly known as chintz and which is used for slipcovers, spreads, curtains, drapes and the like.

The invention provides an improved method of producing the permanent lustrous finish on chintz, and an improved solution for use in such method.

It has heretofore been proposed to subject the fabric to a solution of urea formaldehyde in which the concentration of urea formaldehyde ranges from about to about 30%. The solution of urea formaldehyde is ordinarily prepared in the cold and there is added thereto a catalyst, such as an acid salt (for example, ammonium phosphate) and a softening agent, such as ethyl cellulose. An example of a solution giving satisfactory results, is urea formaldehyde 12 /2 lbs., ammonium phosphate 1% lbs., ethyl cellulose 1% lbs., and water to make 100 lbs.

The solution is applied ordinarily by the use of padder rolls, the lower one of which dips into the solution. Excess solution is removed during passage through the rolls. The cloth is then partially dried at a relatively low temperature, preferably at about a temperature of from 150 to about 200 F. in order to avoid appreciable polymerization of the urea formaldehyde. The drying is carried out in a manner to retain about 10% moisture in the fabric, thus ensuring that the temperature of the fabric shall not obj ectionably rise during the drying operation.

After impregnation and drying of the fabric, the fabric is subjected to either one of two treatments adapted to simultaneously glaze and apply heat to set the resin. The glazing may be effected by the ordinary glazer in which the top roll has a greater peripheral speed than the lower roll, the-temperature being upward of 320 F. The glazing and the setting of the resin are simultaneously accomplished in this operation with the result that the finish is highly glossy and permanent to repeated washings. If a less glossy finish is desired, the impregnated cloth, after drying on a frame to the extent described, is run through a calender of which the rolls operate at exactly the same speed, the pressure employed being preferably in the neighborhood of five tons to the square inch, with a temperature of about 400 F. The cloth may be given two nips or may be run once or several times. According to this method, also, the finishing and the setting are accomplished simultaneously, thus giving permanency of finish.

Where superior strength in the finished fabric is desired, it has heretofore been proposed to add to the solution a coagulatable protein, such as albumen. A solution suitable for this purpose is urea formaldehyde about 12 lbs., 7 lbs., ammonium phosphate 1% lbs., ethyl cellulose 1 /2 lbs., and water to make lbs.

The object of the present invention is to provide a substitute for the albumen which, it will be seen, is used in substantial percentage with respect to the urea formaldehyde, and a portion of which remains in the fabric.

In accordance with this invention, there is substituted for the albumen, an oil, such as sulfonated castor oil, which we have found gives particularly satisfactory results. This oil has the effect of retaining the original strength of the fabric. Apparently the oil affects the physical state of the resin upon polymerization, acting, we believe, to either inhibit the growth of the crystals or to make the crystals less sharp. It also apparently acts to prevent complete or nearly complete dehydration of the fabric by the resin so that, upon washing, re-absorption of moisture occurs and the fabric once more assumes nearly its natural strength.

Additional advantages of the oil are that superficial oil is removed during the washing. It also prevents the res n from sticking to the hot roll or calender which is of particular adva tage when the concentrat on of urea formaldehyde is high, as it avoids damage to the fabric, and the necessity of frequent cleaning and ensures the imparting of the desired glaze.

Among other oils which may be used are those belonging to the class of so-called wetting agents in distinction to materials which are known es detergents (i. e., soaps), and which do not work in this case. More specifically, the oils which can be used in the place of the albumen may be defined as long chain sulfonated oils, that is, chains having more than eight carbon atoms, but whose molecules are not so big as to make the oils waxy. In referring to long chain sulfonated oils, we do not intend to limit it to merely straight chains, as there may also be side chains. The important feature about these oils is that they should have more than eight carbon atoms, but the molecules should not be so large as to make the oil waxy.

We are aware that a great variety of materials have been recommended for use for plasticizing urea formaldehyde resins. However, the oil in this case does not function as a plasticizer and exerts no appreciable action along this line. While we prefer to substitute the oil in whole for the protein, it may be substituted only in part.

albumen I claim:

1. The process of imparting a durable-to-water mechanical lustrous finish to fabrics, which process consists in impregnating the fabric with an aqueous solution containing from 10% to 30% of thermosetting urea-formaldehyde resin-forming material and a. normally fluid water-miscible wetting oil having a chain of more than 8 carbon atoms; and capable of preventing sticking of the resin to calender rolls; drying the fabric to dampness; passing the dried fabric between rolls of a pressure finishing calender; heat setting the resin to the water-insoluble state; and washing the fabric; the amount of 011 being from at least sufficient to prevent sticking of resin in the calender up to substantially 60% of the concentration of the resin-forming materials.

2. The process of claim 1 in which the oil is a sulfonated oil having more than 8 carbon atoms in the chain.

3. The process of claim 1 in which the oil is sulfonated castor oil.

material.

ARNOLD L. LIPPERT.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED HIATES PATENTS Number Name Date 1,559,289 Sibley Oct. 27, 1925 1,998,539 Gams et a1. Apr. 23, 1935 2,103,293 Lippert Dec. 28, 1937 2,108,806 Finzel Feb. 22, 1938 2,148,318 Lippert Feb. 21, 1939 

1. THE PROCESS OF IMPARTING A DURABLE-TO-WATER MECHANICAL LUSTROUS FINISH TO FABRICS, WHICH PROCESS CONSISTS IN IMPREGNATING THE FABRIC WITH AN AQUEOUS SOLUTION CONTAINING FROM 10% TO 30% OF THERMOSETTING UREA-FOMALDEHYDE RESIN-FORMING MATERIAL AND A NORMALLY FLUID WATER-MISCIBLE WETTING OIL HAVING A CHAIN OF MORE THAN 8 CARBON ATOMS; AND CAPABLE OF PREVENTING STICKING OF THE RESIN TO CALENDAR ROLLS; DRYING THE FABRIC TO DAMPNESS; PASSING THE DRIED FABRIC BETWEEN ROLLS OF A PRESSURE FINISHING CALENDAR; HEAT SETTING THE RESIN TO THE WATER-INSOLUBLE STATE; AND WASHING THE FABRIC; THE AMOUNT OF OIL BEING FROM AT LEAST SUFFICIENT TO PREVENT STICKING OF RESIN IN THE CALANDER UP TO SUBSTANTIALLY 60% OF THE CONCENTRATION OF THE RESIN-FORMING MATERIALS. 